Cuba armed itself with Soviet nuclear missiles aimed at the United States which almost brought the world to the brink of nuclear disaster. Castro's communist regime still exists in Cuba, 90 miles from the U.S.

A group of captured Cubans are lined up by Castro's soldiers on the Playa de Giron, Cuba, mid-late April, 1961. They are of the US-backed force of Cuban exiles (known as Brigade 2506) who attempted invasion at the Bay of Pigs. (Photo by Three Lions/Getty Images)

Boston, Massachusetts – A CIA document outlining a Mafia-connected plan to assassinate Cuban leader Fidel Castro for $150,000 is among thousands of Robert F. Kennedy documents made public Thursday, just days before the 50th anniversary of the Cuban missile crisis.

In the 1964 plan, the mob and "patriotic Cuban exiles" eventually settled on a payment of $100,000 for assassinating Castro, $20,000 for his brother Raúl and $20,000 for revolutionary Ernesto "Che" Guevara, plus $2,500 for expenses.

The plan was among some 2,700 pages of Robert Kennedy's documents. The National Archives and Records Administration and the John F. Kennedy Presidential Library in Boston released the documents, which Kennedy compiled as attorney general from 1961 to 1964, offering a glimpse into Cold War decision-making.

Though the documents don't rewrite Cold War history, they do provide insight into the personal thoughts of the era's key figures, historians say.

Kennedy advised John F. Kennedy during the Bay of Pigs invasion and the missile crisis, key moments during his brother's presidency.

The 1961 botched Bay of Pigs invasion sought to oust communists with the help of anti-Castro Cuban exiles and veiled U.S. support. More than 100 members of the CIA-sponsored invasion team were killed and many were captured by Cuban forces.

One CIA document offers a profile of Fidel Castro: It calls him intelligent but "not very stable" and "touchy, impatient and rash."

Another prominent thread throughout the documents is the 13-day crisis over Soviet missiles in Cuba.

On one white page from a meeting on Oct. 16, 1962, the first day of the crisis, Kennedy wrote out two columns: proponents of a blockade against Cuba and supporters of a military strike.

"It's interesting to see in his handwriting who's on which side," said journalist and historian Michael Dobbs, who blogs for Foreign Policy.

The blockade won out.

His title as attorney general "disguised his real position, which was the closest adviser to the president and the person the president trusted most," Dobbs said. "That's the interesting point of this, that he kind of reflects his brother's thinking."

The seven boxes of newly released material include telegrams, reports, meeting transcripts and handwritten notes by Kennedy, some with doodles and quotes in the margins.

"It gives you a sort of insight into what was on his mind, what he doodled," Dobbs said. "It's interesting from a human perspective."

One page, sandwiched between lined pages of notes on the Bay of Pigs invasion, includes a sketch of the Liberty Bell with a summarized quote from a Polish World War II memorial in Italy.

"We the Soldiers of Poland for your liberty and ours give our souls to god, our bodies to Italy and our hearts to Poland," Kennedy wrote in pencil.

The materials are available online and at the Boston library. Some are still classified and aren't available.

The documents' release is important to historians, said University of Maine history professor Nathan Godfried.

"This is the raw materials we use in order to reconstruct the past," he said. "The more documents from different perspectives give us a clearer sense of what happened."